Partial burning apparatus



Jan. 3, 1950 J. M MORRIS PARTIAL BURNING APPARATUS Filed June 24, 1946 John McMnrris, deceasaci 1:5 Helen. B.MCMDTTJIISI' administrairix Patented Jan. 3, 1950 administratrix, Pasadena,-Calif;.,- assignbr to theUnited StatesQhf... Americaas nepresentedby the Secretary oit War q Application June24', 1946,.=Serial N. -.678;748. i.

11 Claim s (Cl. 13 1.67)...

The invention described herein .mawbe Jm l lfS factured and -.used .by. or for" the Government for overnmentakpurposes.without,the payment 0f anyiroyal-tyq thereon-q Therpresent invention; relates to rocket motor testing;equipmenteand,emore particu arly, to I apparatus .i or partially ;zburning the propellant; charge-ma rocket motor: [to permit examination of- .the state of zthegoharge .at any predetermined; time after; ignitiom I As-is wel-l-.known;v itis. customary to carryout, static testson rocketgmotorsgto developjriformation as to. periormancecharacterist cs f t prope1-lant;.charge;.-,- Among the tests carried out for; example, isto plotthe pressure-timecurve durin burning f of. theipropellant .within' the :motor.v 1112 such.- a test, thez rocket-v motor .is mounted inha; fixed positiom. usually vertically-With ;-the; nozzle; pointing upward, whereupon the. rop llant.- charge-isignitedand readings vare taken .of the pressure:generated; within theg'motcrat regular;- timemt.erva1s; .during. burning.,. Heretofore; inthe operationof; such;tests;,.it* has,.not;bee n possi.-., ble 1 to stop the. burning. of l the gpropellanti chargealien-intermediate.stagelto permitinspectionpf the;-charge.as an. aid;=to. determining. the; cause; of-.;.any =.irregularities i discovered during testin It .is ,an; object :-of.-;--.th'e.z-inV.enti0ntov provide; means forrstoppinghthe burning .of the'lpropellanta charge in aarocket motor;.-at any predetermined time after ignition;

It:is another obj ,eot of the invention-to provide means .topermit ejection-of thezpartially burned-lpropellant charge from the roeketm torend-to receive. .the same 1 without, mechanical dama e-y A turther; {object of; the-invention; iszjto ,1aecu-n p h e zforegoi-n iectswwithout inter er n with :the. simultaneous testing of the-performance of, the-propellant; charge such as, for example the taking 0f pressure --readlngs. during burning Other objectswill. beeppare ti m th e o, ing-- disclosurev of a specific; embodiment 1 of; the inv ntion res shown e;a i mp anvin e rawm in s in w ich the-sin lerfieureis arQnhr em pa ally i c o s-.see ion;; -.t ew-apparetuswi h? a .-r. k m tor;;ri t led r o R fer i e edrar nes; h za paratu sheen: therein mprises a avy plate p rt whi h is cun a. izontal y m.ean; brackets 2 above a tank-i "i adapted to ,hold a; 5. quantity of noninflammable liquid. such as ater 4; 7 As will be reXplained mor-e fully hereinatten it also is desired to providealayerof sand 5 in thee bottomefth tanka .Th ou arwrifieefi n the. piste situated abor hes anls rithete e ecdssa collar- '5; Which-is secured to-the plate I. by means adapted; to receive the. threaded end a of, a.

standard rocket motor H Whenthe cylindrical tube-l2 ofthe mot or l l isser ewedztherein, the motor- H is fixed in a substantia 11y.vertical position with. 1 its 1 discharge no zz 1 e.. l 3 .extending u wa Y Within the collard, there is a. shoulder 14.,

against which an end disk I5 is adapted to so as to close ioli ,the bottom end of the X rocket motor? tub 12. -The. end disk I5 is held in place 1 1; a;spaeer.ring l 6 and endspla te. I I the latter being secured to the. collar by means pfshearbolts; 18,, The-spacer ringflfi ,form s-,a-cavity, ISIrJQev tween the end disk I5 and endplate ll to receive, a gunpowder charge preferably within ametal container it. An ignition. wir 2 1 extending o -eh anlo fi e inth end e fl is o ded. for- ;setting ,olf the gunpowder charge as. explained. in morefdetail hereinafter...

The-rocket. motor i i .may .he. any-oi the stand ard types. having the ,u sual propellant charge .as,..

for example c eer more,extrudedBallistite tubes 21 anda retaining Venturi member 22 having an; expansion passage l3. 'Anignitionwire 23-15 pro vided fprigniting the propellant charge Min" the, .u a man e In order to permit measurementsof-the prese. sure. generatedin the rocket motor. duringburning .pf thepropellantcharge, theremay be. pro vided ..a, small orifice. 2.6- adjacent. the upper, end; of the tube to whichmaybe secnred, .for example by brazing, anoutlet tube 25 .to which. apressure gage. (not shown in the, drawings} may, be; connected;

e'i-table ean mare .tr f f r zthe .circuit throughignition wires .20 and 2 3 I in pre; determined sequence, v{such means are indicated. geneigally-at 2.? as ,a commutator .or circuit closing. d et/glee ,sup plie with potential; from .a source 2.8, and operablietofirst closethe circuitthro-ugh 23f ,to ig te hemope l naehe z e 4 na hem Di e e i e tim t r to, m ee at ei in-. ea fitw ensc er 2 I b n a ll u ed. enitie c .ne w v c arg u es he-bolt i Mo e p ured s er i f r s ef thee-rid plate l1, spacer ,ring, l6 and end disk l5,- as ,Wel1 v as the Ba llist ite tubes 2 nit 1' the. rocket. motontoiall. into-,the: tank ,3. The ..resulting abrupt pressure reduction, in the. motor .extin s, wishes hei-e epe leetph r et eth??? t-r i eiee nia.d snzedr t iallr rntebi it ea To prevent premature ignition of the gunpowder by hot gases leaking from the rocket motor past the end disk IE, it is preferred to seal the gunpowder charge and electric squib in a small metal can 26 which will fit within the cavity 19.

The design of the tank 3 does not appear to be critical. Successful experiments have been carried out, for example, using a round receptacle made of inch steel, having a diameter of about 14 inches and a height of about 30 inches. A layer of about 5 inches of sand in the bottom of the tank plus a Water depth of 18 inches has been found to be adequate to protect the ejected metal parts and the partially burned propellant charge from mechanical damage.

It thus is seen that the testing apparatus of the present invention permits the operator to extinguish the propellant charge at any desired time after ignition and to receive the partially burnt charge in an undamaged condition for visual examination.

It will be apparent that the specific embodiment of the invention described above Will be subject to variation by one skilled in the art within the scope of the invention, and all such variations are intended to be included within the scope of the following claims.

It is claimed:

. 1. Apparatus for partially burning a propellant charge in a rocket motor comprising a tube having a nozzle at one end, said apparatus comprising means for mounting said motor in a fixed position, removable closure means for closing the end of the motor opposite from the nozzle, retaining means for holding the closure means in gastight relation over the end of the motor opposite from the nozzle, explosive means for removing said retaining means and means igniting said propellant charge and said explosive means in predetermined sequence.

2. Apparatus for partially burning a propellant charge in a rocket motor open at one end and having a nozzle at the other end, comprisingmeans for mounting said motor in a fixed substantially vertical position with the nozzle extending upward, removable closure means for closing the open end of the rocket motor, a plate for positioning the closure means at the open end of the motor, an explosive charge between said closure means and said plate, means adapted to hold the plate and closure means against the thrust engendered by burning of said propellant charge but rupturable by said explosive charge.

3. Apparatus for partially burning a propellant charge comprising a rocket motor having a nozzle at one end, means for mounting said motor in a fixed substantially vertical position with the nozzle extending upward, releasable means closing the lower end of the rocket motor and retaining a propellant charge therein against the thrust engendered by burning of said charge, means for releasing said releasable means a predetermined time after the propellant charge is ignited and a receptacle for containing liquid disposed below the rocket motor for receiving said releasable means and the partially burnt propellant charge expelled from the rocket motor.

4. Apparatus for partially burning a propellant charge comprising a rocket motor having a nozzle at one end, a propellant charge in said motor, means formounting said motor in a fixed substantially vertical position with the nozzle extending upward, removable closure means for closing the lower end of the rocket motor and retaining said propellant charge therein, retainer means for positioning said closure means in operable position, an explosive charge for removing said retainer means, means for igniting said propellant charge and said explosive charge in predetermined time sequence, and a liquid-containing receptacle disposed below the rocket motor for receiving said partially burnt propellant charge upon removal of said closure means.

5. Apparatus for partially burning a propellant charge comprising a substantially horizontal plate having an orifice therein, a rocket motor open at one end and having a nozzle at the other end, means for mounting said motor with the open end over said orifice and with the nozzle extending upward, a removable disk for closing the open end of the motor and for retaining a propellant charge therein, a retainer secured to the plate by rupturable bolts for positioning the disk at the open end of the motor, an explosive charge between the retainer and the disk for rupturing the bolts upon ignition so as to separate the retainer from the plate and permit the disk and partially burnt propellant charge to be ejected downwardly from the motor, a receptacle containing sand and water for receiving said retainer, disk and partially burnt propellant charge, and means for igniting the explosive charge a predetermined time after the propellant charge is ignited.

6. In an apparatus for partially burning a charge of propellant in a jet propelled device having a casing open at one end and provided with a nozzle at the other end, said apparatus comprising a frame, means mounting said casing in fixed' position on said frame with said nozzle directed away from said frame, a closure for said open end, frangible means holding said closure in position closing the end of said casing, force applying means operable to break said frangible means, means igniting said propellant charge and operating said force-applying means in predetermined time sequence and means responsive to breakage of said frangible means for extinguishing the burning propellant.

7. In an apparatus for partially burning the propellant charge in a rocket motor having a nozzle at one end, means rigidly mounting said motor in a normally vertical position with the nozzle directed upwardly, removable closure means for the normally open end of said motor remote from said nozzle, frangible means securing said closure means in gas-tight relation with said normally open end, and explosive means operable on detonation to break said frangible means and permit said closure means to drop off.

8. In a device for partially burning the propellant charge of a rocket motor comprising a casing containing said charge and having a nozzle at one end, a liquid container, a frame mounted in superposed relation over said container, means mounting said casing in said frame in position over said container and with said nozzle directed away therefrom, a closure for the other end of said casing, frangible means holding said closure in gas-tight relation with the end of saidcasing remote from said nozzle, an explosive charge arranged, when detonated, to break said frangible means, and means for igniting said propellant charge and said explosive charge in predetermined time sequence, whereby the partially burned charge is deposited in said container in response to breakage of said frangible means.

9. In an apparatus for partially burning the propellant charge within a, rocket motor having a nozzle at one end, a support having an aperture therein, a liquid container, means mounting said support over the open upper end of said container, a collar within said aperture and secured to said support, the bore of said collar having a downwardly-facing peripheral shoulder, the end of said motor remote from said nozzle being threaded into said collar above said shoulder, a cover disk within the bore of said collar and seating on said shoulder to form a gas-tight joint, a ring in said bore beneath said disk, a plate, frangible bolts passing through said collar and plate to hold said plate against said ring and said disk against said shoulder, an explosive charge within the cavity formed by said disk, ring and plate, and adapted, when detonated, to break said bolts whereby said propellant charge may drop into said container.

HELEN C. MCMORRIS, Administratria: of Estate of John McMorrz's, De-

ceased.

BEFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,489,566 Webster Apr. 8, 1924 2,111,315 Damblanc Mar. 15, 1938 2,448,203 Africano Aug. 31, 1948 2,464,179 Hickman Mar. 8, 1949 

